Vacuum fuel-feed device



C. S. BURTON.

VACUUM FUEL FEED DEVICE.

APPLICATION nuzo AUG-16.19%.

1,348,084, Patented July 27, 1920.

2 SHEETS-SHEET I c. s. BURTON.

VACUUM FUEL FEED DEVICE. APPLICATION man nums. ma.

1,348,084, Patented July 27, 1920.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

CHARLES S. BURTON, 0F OAK PARK, ILLINOIS. ASSIGNOR TO STEWART-WARNERSPEEDOMETER CORPORATION, OF CHICAGO. ILLINOIS. A CORPORATION OF VIR-GINIA.

VACUUM FUEL-FEED DEVICE.-

Specification of Letters Patent.

Patented July 27. 1920.

To all 'tIIHI/Il 2'! may eon/era:

lie it known that 1 (lnaumcs S. liUltlHN, a eitizen ol' the l nitedStates, and a resident of the village of Oak Park, in the eountv ol'(ooh and the Slate ol lllinois..

have invented certain new and useful llllprovements in Vaeuum Fuel-Feedlleviees, ol' \vhieh the following is a sptwiliealiou, referenre livinghad to the at'eompauyiin; drawings, forming a part thereof.

The purpose of this invention is to hrovide an improved eonstruetion ofvacuum fuel Feed deviees for internal eomhustion engines \vhieh shall hepartieularly adapted for furnishing the Fuel lifted from a lowlevel mainsupply tankwvhen the suction availahle is low in small quantities andshort intervals as it is thus lifted. and othen wise to adapt the devieeto have greater feeding' and storage eapaeity wilhin given over-alldimensions. ll eonsists in the elements and features ol eonstruetionshown and deserihed as iudiealed in the t-laims.

In the drawings;

Figure l is a vertieal seetion ol' the upper portion eomprising theentire valve eontrolling ('oilneeliions and operating float Ill a devieeembodying this inventioin th lower part of the float ehamher and thereservoir ehamher heing hroken away.

Fig. is a seetion in a plane at right angles to that of Fig. 1, showingthe same construction, with a middle portion oi the vertieal extent ofthe reserve ehamher hroken away to reduee the eompass of the view.

I Fig. 3 is a seetion at the line Zl3 on ig. lis a section at the line44 on Vi". L looking upward.

ig. 5 is a detail seetion at the line 5 on Fig. 4. looking radiallyinward.

The prohlem the solution oi whieh is attempted in this invention, is toadapt a var uum fuel t'eed deviee of the type eomprising a vaeuumehamher and. a reserve ehambe! and whieh derives the suction foroperating it from the manifold of the engine \v-hirli is to he served,to release and deliver to the reserve ehamher the liquid fuel whieh issucked up from the main low-level supply tank into the vaeuum eha uhenat the shortest praetiea le intervals when the eonditiou is such thatthe supply is low and the suelion light; these two eonditvions heingusuall v eoiu-nrrent, that is the. suetion hein; light nhenevel'lheeonditions have for some time heen sueh as to reduee th revserve supplyto :1 low point.

In the familiar lleviees for this purpose now in eonnnon use. there isemployed what is known as a snap aetion l'or eausing a quiek reversal ofthe situation of the valves whieh eontrol the (lfllllllltllltt in thevaeuum ehamher of atmospherie pressure or suetion. This snap aetion isconstructed to Cause the ehane'e of level of the liquid in the vacuumehamher, hy means of the tioat therein, to shift eertain valvtwlperatinglever eonneetions with \vhieh the snapsprin;: is conuerted, as the floatrises or falls. moving one eonneetion of the spring until its line ofreaetion extends past the tulerum of the, le\er eonueeled thereto. thespring at this stage heine' at maximum tension, and therefore reaetingto eontinue the throw of the levers in the direetion in \vhieh they haveheen moving to thuwteusion the spring. In slu-h strlu'tlll'e thereaeting spring furnishes the sole meehanieal three for moving the valveor valves to he shifted; and sinee the valves in question are held bythe suction in resistanee to the movement to he thus auseth the springmust he'eonstrueted to have at this stage of maximum tension adequatetension to move the valves against the maximum suetion: heeausoohviously the spring tension is constructional, and will not he ehangedhy the ehanging conditions of suelion. but must he adequate for theextreme eonditions whieh may arise.

Now in any eonstruetion in whieh the valve levers are actuated only hythe springs and the lloat obtains no direet'aetion on thevalve-operating eonneetion, inasmueh as the tension of the snap-springis overeome hy the huoyaney or weight of the float in musing thereversion of the valve situation. and the operative'huoyaney oroperative weight ol' the lloat depends on the extent to whieh the lloatis depressed in or held up out of the liquid hy the spring resistant-ethere eannoi he any variation in the height to \vhieh the liquid mustrise or the depth to whieh it nmst fall in order to reverse the valvesituation: and the quantity of liquid taken in and delivered at eaeheyele oi the operation of the deviee, must always be the same whateverhe the suction operating, and whatever the condition of the device as toreserve supply. It follows that in such a structure the purpose of thepresent invention, namely, as above stated, to adapt the device toreceive and deliver small charges to the reserve chamber, so as to makesuch deliveries quickly when the reserve supply is low, can only beaccomplished by making the structure so that small charges shall bereceived and delivered at all times and under all circumstances,

It will also be evident upon consideration, that with a given rise andfall of the liquid level in the vacuum chamber requisite for reversingthe valve action, the frequency of such change, which depends upon thequan tity of liquid going in and out to make the change, can beincreased,-that is the quantity can be reduced,*by reducing the crosssection of the vacuum chamber in which the liquid level rises and fallsin such change, or by reducing the amount of such change of level, thatis, the vertical dimension of the space thus filled and emptied. And itwill be further observed that the cross-section of the space in thevacuum chamber thus filled and emptied depends upon the difference incross-section of the chamber itself and the cross-section of the floatoperating therein, and can be reduced, therefore, only by, causing thesetwo cross sections 0 approximate each other, that is by reducing thewidth of the space in the chamber around the float. 'And it will befurther observed that the reduction of the change of level occurring ateach reversal of the valve situation with a float of a givencrosssection, can be reduced onl v by reducing the spring resistanceagainst which the float operates.

All these considerations enter into the problem and into the solution ofit which is embodied in the structure shown, which will now bedescribed.

In the structure shown in the drawings, 1 is the reservoir or reservechamber of the device; 2 is the vacuum chamber which is suspended in thereservoir or reserve chamber, 1, having for that purpose at its uppercod :1 horizontal flange, 2, which laps upon an interiorly protrudingflange, 1, of the chamber, 1. 3 is a cap member which coversbothchambers and has a flange, 3, which laps upon the margins of theflanges. 1 and 2, which are bound to said flange, 3". by bolts, (1,thereby securing the three principal members of the structure firmlytogether, suitable packing being interposed between said flanges formakin the joints liquidtight. 4 is a check va ve past which the liquidis discharged into the reserve chamber.

5 is a buoy in the vacuum chamber conthe stitutiug part of the means foralternating the dominance of suction and atmospheric pressure in thatchamber, hereinaftcr more particularly described, being the means forreversing the valve situation upon change of level of the liquid in thevacuum chamber. Th s buoy is calculated as to relative weight and volumeto balance upon submersion in the liquid fuel to the depth indicated bythe dotted line, at, on said buoy, and to have operative buoyancyadequate for overcoming the resistance of the snap-action springhereinafter described, upon being further submerged to the line, a, andto have operative weight suiiicient for overcoming the resistance of thesnap action spring upon being nil-submerged or held up while the ll( uidlevel falls to the line, p.

The buoy, 5, is suspended in the vacuum chamber by means of a bell cranklcvcr, (1, whose, horizontal arm is in the form of a bail embracing thebuoy from one side, and whose vertical arm extends downward from thefulcrum of the lever which is t'ulcrumed on the wall of the vacuumchamber most conveniently at 7 on lugs 7, 7, depending from the capmember, 3. 8 is the snap-action spring which in the constructionillustrated. is a compression spring coiledabout a guide link or stem,9, which is pivoted by its head, 10, at its lower end between lugs, 7-7,which depend rigidly from the cap 3, the upper end of thi stem passingjloosely through the cross-neck conmeeting the two parallel downwardlyextending arms. 6, of the bell-crank-lever 6, so that said link or stem9 has sliding pivotal engagement with said lever arm. The bail member ofthe bell-crank-lever engages trunnions 5 at opposite sides of the float,the chord of the arc of movement of the axis of the pivotal connectionof'the lever to the fioat at the trunnions being substantially vertical,so that the lateral or horizontal displacement of the float in the swingof bell-crank-lever is negligible. 12 is a second bail which embracesthe float vertically, extending up around the' lower end of the floatand having its ends engaged with the trunnion, 5 by which the bell cranklever is connected to the float, the ends of the bail, 12, being slottedat 12', for their engagement with their trunnions to provide for lostmotion between the float, and thereby between the bell crank lever,andsaid bail, 12, the length of the slots and the extent of this lostmotion being designed to be substantially the amount of the throw of thebell crank lever at the ends of its bail member-from th intermediateposition at which the snap-spring is alined with the bell crank leverfulcrum, to the limit of the throw caused by the spring in eitherdirectioni' from this middle position: The bail 12, is pivotallyconnected with a lever 13, which extends across under the lower end ofthe buoy, 5. being itself in the form of a bail, that is. having bothends upturned alongside the buoy, one end being fulcrumcd at H on thewall of the vacuum chamber, and most conveniently on the lower ends ofthe lugs, 7, 7, depending from the cap 3. The other end which extends upto substantially the same level as the tulcrum,that at the rind-positionof thc' throw of the lever is rigidly attached to a substantiallyhorizontal cross-head, 15, which engages looselyg but. substantiallywithout lost motion except as slight pivotal motion is permittcd,-lhcstems of the an! lion controlling valve, to. and the atmos phere inletvalve, 17, controlling respec tively, the suction outlet, 18, andatmosphere inlet, it), formed in the cap member. 3, which closes thevacuum chamber at the top,

For obtaining the desired compactness of construction, so as to havewithin given dimensions over all a maximum storage capacity of theentire device, and at the same time the possibility of occupying saidmaximum capacity with the liquid, and adapting the device to deliverminimum charges with maximum Frequency from the vacuum cham be! to thereserve chamber. the construction shown involves certain detailsrequiring particular n'iention.

Space in the vacuum chamber obtained for the springsnap action involvingthe bell crank lever with its downward cxtcnding arm (3, the spring 8with its guide and stop and space for the swing or throw of the bellcrank lever arm and spring. and all this with the minimum enlargement ofthe liquid capacity of the vacuum chamber around the float, by formingthe vacuum chamber with a pocket or outwardly eX- tending recess 30 atone'side, intruding into the annular space between the outer wall of thereserve chamber and the wall of the vacuum chamber at the upper end ofsaid space at one side, this pocket being radially extended as far as itmay be consistently with leaving room for the flange 2 of the vacuumchamber to seat upon the inturned flange 1 of the reserve chamber, asalready described. At the opposite side of the buoy, the vacuum chamberis provided with a similar pocket 20 dimensioned radially substantiallythe same as the pocket 30, but ex tending cirrumfcrentially with respectto the vacuum chamber and reserve ehambera sullicicnt distance toaccommodate the atmosphere valve 17, suction valve l6, and the portsrespectively which they control, with adequate distance between them toaccommodate on the outside of the chamber above the shoulder hereinaftermentioned. the neoessauv fittings for connections with the said ports.The cap member 3 contains the up per part of the vacuum chamber which isreduccd in diameter so as to exceed the di-- amctcr ol' the float onlyby a sullicient amount to a fl'ord necessary clearance for the freemovement oi the latter up and down. This causes the said cap 3 torequire at its lower end for its junction with the members 1 and 2 ofthe structure, the flange 75 abo\e mentioned, hose outer diameter is thesame as the outer diameter of the member 1, so that it laps upon the topof the marginal flanges of said other two members i and :2. This flangethus overhangs the pockets iii] and 2 and through it there are Formedthe two ports mentioned, viz: suction outlet port 18, atmosphcrc inletport iii. and said cap is formed with a segmental boss ii of sullicicntcircumtercntial extent to embrace these two ports which are bored in theboss from the upper end. the rods of the bores being plugged as shown,and the bores being tapped laterally for the necessary connections,namely the suction pipe 25 leading to the su tion port, and theatmospheric inlet pipe :18; and the same boss 3* is extended inwardlyover the head of the cap to ac commodate the fuel inlet port 21. whichis bored into the boss radially to meet a vertical bore from the underside of the cap, as seen in dotted line in Fig. 5. and in full line asto its mouth in Fig. 4. The outer end of this radial bore allordsconnection l'or the fuel supply pipe 12 which leads l'roin the maintanlt. This boss is extended at 27 over the flange radially, to overhangthc annular interval bctwccn the vacuum chamber and the reserve chamberto all'ord opportunity i'o' atmospheric connection by the duct 27, fromthc top of the rcscrvc chamber into the atmosphere inlet passage leadingto the vacuum chamber above the atmosphere valve. as has been customaryin devices oi this character heretofore, for convenienceol' coimectingboth said air passages with a single air pipe 28 which may extend to anydesired height or to any desired point at a distance, for the dischargeof any vapor ot' the liquid fuel which may be generated in either of thechambers under conditions causing the device to become highly heated.

The operation of the (flevice in view of the construction described andthe din'icnsions of the float for operative buoyancy and weight as abovedescribed, is as follows:

Assuming the entire device empty and connected with a suction resultingin producing a partial vacuum in the vacuum chamber and causing theinflow of liquid fuel from the main low tank into the 'acuum chamber,the

latter being filled to a level which will first down by the resistanceof that spring becomes submerged more deeply notwithstanding it will befound to have been lifted to the position shown in dotted line in Fig. l(but less. it will be observed. than the rise of the liquid level), at\vhieh position the snap-action spring 8 is under the maximumtension.the bell erank lever arm (3 being alined with said spring.

.\t this position the excess oi. rise ol the liquid level from thebuoy-lmlancing position indicated by the line, m. over the rise of thebuoy during said rise of the liquid will be an amount dependent largelyupon the tension of the spring. 8. l'pon .the liquid rising anappreeiable amount above this level. the reaetion ol' the snap-actionspring H \vhieh oeeurs upon the lever arm ('r being carried past theposition of alinemeut with the sprin will cause the buoy to be lifted tothe position shown by line, 1', in Fig. 5, unless the su tion operatingupon the at mosphere valve 17 whirh is up to that time. closed. (thesuction port and valve being open). is more than can be overeome by thereaction of said snap-artion spring. it is intended that this springshall be of sneh a tension as to open the atmosphere valve un derconditions of the lowest suction under which the device will properlyfunction or is expected to be operated. or at least. under somerelatively low suction. ll the suction is still lower than this. thevalve will all the more certainly be opened by the re-artion ol' thespring at the point indicated. lt' the suetiou is greater than theminimum at whieh the snap-action spring is designed to operate for suchopening of the valve. thl! snapaetion connection being carried past.t'ie center so that the spring is in position to react. the furthermovement of the bell crank lever and the further rise of the float willbe halted until further rise of liquid in the 'aeuiun chamber. causingdeeper immersion of the buoy in the liquid and greater ell'eetive,buoyancy of the float. renders that buoyancy sullieient to overcome thesuction on the at mospl ere valve: whereupon. sueh point being passed.the valve will yield and snap open to the full extent. the bell (ranklever completing its swing in the direction for such opening and thefloat rising to the position shown by dotted line in Fig. 52. which isthe high position of the float and the limit of its upward range ofmovement.

The 'alve situation being reversed by this movement of the float. thatis to say. the suction valve being closed and the atmosphere valveopened. the contents of the vacuum'ehamber will descend by gravity pastthe outlet valve 4 into the reserve chamber 1. As the level of liquid inthe vacuum chamber falls. the buoy will fall with the liquid level butsubstantially half as fast as the level alls. because it will fallagainst the resistance of the snap-action spring 8, until by thisresistance the tloat has become nnsulunergtal by being held up while theliquid level was falling to the line 71 on the lloat; and upon thefurther fall of liquid an apprta'iable increment below this point, theaeeumulatwl etl'eetive weight of the float overcoming the resistance ofthe snap-action spring H will earry the bell erauk lever arm (3" pastthe position of alinement with the spring. and the spring will completethe throw carrying the bail member of the bell eranlt lever down andpermitting the. float to deseend to the low-level position shown in talllines in Fig. 1. again reversing the valve situation. that is. ('losingthe atmosphel'e valve and opening the sur-tion valve. lllhllllll'll asin this action the suetion valve will have to be pulled oll' its seatagainst the uetion. it will be seen that it' the surlion hold on thisvalve is greater than can be overcome by the reaction of the snapspringH. the descending movement ol' the lloat will be halted at the po itionol' maximum tension of the spring. that is to say at the point at whichthe trunnions 5" reach the lower end ol' the lots. 12. in the bail l2,and the parts will there remain until i'urlher l'all ol' lhe liquidlevel has rendered the tllt'tllYt' weight of the lloat by reason of itsfurther unsulnnergen e. sullieient to overcome this suetion pull. thenthe action will be completed. the [hall eompleting its deseent to thelow limit above mentioned. it, will be seen tla-rel'ore. that the ehangeol' liquid level ori-urring in earh cycle ol' the operation of thedevice will have a mininnnn determined by the tension of the .\llil|]sprin \Illtl tension being designed. as above stated with reference to aeertain assumed minimum suction operating from the valve: and that itwill have a maximum determined by the deepest snlunersion and thehighest emersion ol' the buoy. the submer sion for said minimum beingwhen the buoy is positioned at the halting point in the risingmovement.-that is. when the snapaetion spring is alined with the bellt'l'illlh' lever arm. tl. a'nd the emersion for said minimum being whenthe lloal. reaches the halting point in its descent. The maxin'uunchange of the level will therefore be the full height of the lloat.while the minimum will be the distance between the lines. 'I/L and p;and that the minimum change of level will' occur under eonditions of lowsugion. It will be seen also that the continuance of conditions of lowsuction while the reserve chamber contains a low reserve supply, thatis, anywhere below the bottom of the vacuum chamber. will result incorresponding frequency of repetition of the filling and disehargingaction of the vacuum chamber; that is to say, the vacuum chamber willmake deliveries at short intermum lifting force, and providing a pocketfor this upper end portion of the float entirely above the level of saidvalved. ports, am] by reducing the diameter of the chamber at this pointto the minimum which will accommodate the tloat and avoiding thepositioning of any of the operating elements in the space around thelloat which would increase the retplircmcnt of the diameter, for theiraccommodation, there is provided the shoulder above which all the tluidconnections can be made. so that these lluid connections are all broughtwithin a maximum compass over-all which is no greater than required forthe chambers without these connections.

'The total result of the several dctail fea tures of construction abovepointed out is that the entire device within a given compass over-all inboth vertical and horizontal directions has substantially the maximumcapacity for the liquid fuel under the conditions under which it may betilled to maximum capacity. and has a pre-determincd minimum ol' theliquid charge rcceivcd and delivered at each cycle ol the action underthe conditions requiring frequency of such action.

I claim:

1. In a vacuum t'nel teed device comprising a. vacuum chamber and areserve chamber, the vacuum chamber having the following lluidconnections. viz: (1) a fuel supply inlet. a fuel supply outlet to thereserve chamber (3) a. suction outlet. and (l) :l] atmosphere inlet;means in the vacuum chamber for alternating the dominance of suction andpressure comprising a buoy mounted for movement by change ol liquidlevel in said vacuum chamber; a valve device controlling certain of saidtluid conncclions. and operating connections to the valvc device fromthe buoy comprising a snapaction spring. the buoy being positively (Ulkncctcd opcratively with the valve dcvite in dependently ol' thesnap-action spring; said operating connections containing a lost nu tionjoint; the snap-action spring being con nccted l'or its tcnsiouing bythe mmemcnt ol' the buoy through the range 01' said lost motion.

'1. lit a construction such as dclincd in claim l. the buoy bringpivotally suspended and lnning two connections from its sits ]H'llHlu!lpivots. ouc consisting ot a lcvcr ha\ ing its fulcrum support on thevacuum hamber wall. the snupaclion spring opcratiug on said lcvcr. lhcolhcr cxlcudiug to the valve and containing the lost motion joint 3. ina construction defined in claim 1 foregoing, the buoy being carried bytwo lifting elements the snap-action spring being connected foroperating on one of them, and the other containing the lost-motionjoint.

4. In a construction defined in claim 1 foregoing, the buoy beingpivotally suspended, and having two connections from its suspensionpivots. one of said connections com prising a bail embracing the buoyhorizontally. and the other comprising a hail embracing it vertically.

5. In a construction delined in claim 1 foregoing, the buoy being pivotally suspendcd and having two hails for so suspending it.-one bailembracing it vertically and the other bail embracing it horizontally,the vertical hail being positioned and connected to embrace the buoyfrom below by upward extending arms: whereby the same and theconnections therefrom 't'or operating valves are accommotlated in spacenecessarily providcd tor the liquid. to the avoidance of specialprovision for such acconunmlatiou.

('1. In a construction delined in claim 1, foregoing. the buoy beingpivotally carried, the carrying means comprising two bails. oneembracing the buoy horizontally and the other embracing it. verticallyfrom below upward, the operating connections for the last mentioned bailto the valve consisting of a lever t'ulcrumed on the. vacuum chamberwall at one side of the buoy and having its engagement with the valve atthe o po it ide. and having a droop to reach the bail connection andaccommodate the lloat between its fulcrum and its valve conucction.

T, in a construction defined in claim 1,

l'oregoing. the vacuum chamber being eX- tclulctl and protruded abovethe top of the reserve chamber with reduced diameter to acconnnodatc thebuoy atv the elevated posi tion of the latter. the valved lluidconnections being made at the shoulders which results around suchextension.

H. ln a construction such as defined in claim l. the vacuum clnunbcrbeing extendcd and protruded abmc the top of the rescrvc chamber withreduced diameter o no conunodate the buoy al the elevated position ol'the lattcr. valve lluld connections being made at thc shoulder resultingaround such extension,

In testimony whcrcoi'. l have hereunto et in) hand this 115th day of.\llglt$t. 1918, nt hi ugo. lllinnis.

('ll,\ HLICS S. BURTON.

